一、问题来由在一次网络教研中,有教师提出一个问题:下面这道题有几个解?如图1,⊙O是正方形ABCD的外接圆,点P在⊙O上,则∠APB的度数为___________.关于这一问题,有的教师认为是一解,有的教师认为是两解.观点一的理由为:“如图”本身也是一个重要的条件,不可忽视;观点二的理由为:题目所给的只是示意图,其中,点P的位置是不确定的,所以点P也可能在 First, the problem arises in a network of teaching and research, there is a teacher to ask a question: The following questions have several solutions? In Figure 1, ⊙O is a circumcircle of the square ABCD, point P in ⊙O, then ∠APB The degree is ___________. On this issue, some teachers think that it is a solution, and some teachers think it is a solution. The reason for the first point of view is: “Figure” itself is also an important condition, can not be ignored; The reason is: the title gives only a schematic diagram, where the position of the point P is uncertain, so the point P may also be